listed some 450 different animal species, including dogs and wolves, as having been observed having homosexual fun and games
Actually homosexual behaviour has been observed in around 1,500 species from insects to mammals, although it is usually more accurate to talk about bisexuality among non-human animals. Very few species are known to exhibit exclusively homosexual behaviour, even when females are available. A few exceptions have been found including some domestic sheep.
Interestingly they show the same anatomical differences in an area of the brain called the hypothalmus that has been observed in homosexual men.